We finished an ISCO round on a TCE source in May 2024 and saw wells at 12–18 ft bgs drop from about [redacted]/L to [redacted]/L, then rebound to about [redacted]/L by month 6 — textbook back-diffusion from the silty matrix. I lean toward mapping mass storage and vertical gradients with HRSC (Waterloo APS or depth-discrete passive samplers) before more oxidant; has that approach pushed you toward sustained biostimulation or targeted thermal, and over what window did you confirm a real drop in mass flux?